AbstractBackground and objectivesBoza is a traditional cereal‐based (millet, corn, rice, etc.) and fermented beverage with sweet‐sour and bread‐like taste. It is a low‐alcohol and high‐viscosity beverage. In this study, it was aimed to develop a new gluten‐free boza formulation consisting of chia (100%), quinoa (100%) and chia + quinoa mixtures (50% + 50%) and determine its characteristics. For this purpose, physical, chemical, rheological, microbiological, and sensory properties of gluten‐free boza were researched.FindingsThe highest protein (6.44%), ash (0.89%), pH (3.24%), oil (0.84%), and mineral content were determined for the chia boza samples. The highest lightness (L*) and yellowness (+b*) values were determined in quinoa boza samples (p < .05). The highest soluble dietary fiber (1.22%) and insoluble dietary fiber (1.25%) contents were determined for chia boza samples. The dietary fiber content of quinoa and chia + quinoa boza were similar (p > .05). The highest lactic acid bacteria (9.03 lab log cfu/g) and yeast mould counts (6.72) were observed for quinoa boza samples. Rheological analyses results showed that all boza samples showed pseudoplastic behavior with a flow behavior index ranging from 0.66 to 0.98. The highest viscosity belonged to chia‐containing samples.ConclusionsConsidering sensory analyses, quinoa boza samples got the highest general acceptance in terms of color, sensory, flavor, and consistency according to panelists results.Significance and noveltyGluten‐free boza production with high nutritional value and acceptable taste can be achieved. For the first time, chia and quinoa were used as raw materials in the production of boza.